There are so many things to keep in mind when you're out in the sunshine. From remembering when the sun is at its strongest, to re-applying sunscreen frequently; a trip to the beach could end up a little less relaxing than you first imagined. But, sun safety advice is there for a reason and it's definitely a good idea to educate yourself on things you don't know about skin cancer, as well as how to protect yourself.

Of course, the main barrier of protection we humans have against skin damage is sunscreen. However, there are some important things to remember about sunscreen. Aside from the fact that sunscreen can expire and you could unknowingly be walking around without a barrier to those harmful rays (yikes!), you might even be allergic to sunscreen. Although this may sound pretty terrible, there are many weird things people can be allergic to that could prove far more troublesome to the sufferer, than certain types of sunscreen — it's always best to look on the bright side.

"By adulthood, most of us have an intuitive sense about how sensitive we are to sunshine," says board-certified dermatologist Dr. Janet Prystowsky. "We also may already know if we are allergic or otherwise sensitive to certain sunscreen chemicals," she adds.

"If you have a new sunscreen, you may want to apply it to your skin in your elbow’s ‘pit’ for a few days to see if you have a skin irritation or an itchy reaction," explains Dr. Prystowsky. It's always a good idea to test drive beauty products that are new to you, especially if you suffer with sensitive skin.

"This test isn’t foolproof, though," warns Dr. Prystowsky, "you might be fine with the elbow test and then still have a problem when you go out into the sun with your new sunscreen. This is because you can get a photoallergic reaction to it."

"In other words," she elaborates, "you may only have a negative reaction to some sunscreens when you’re in the sun. So you should also apply the new product to a small area of your skin when in sunlight to see if you have a photoallergy to the product."

In order to ensure you don't have an allergic reaction on vacation or at the beach — not an ideal situation to find yourself in — try out this sunscreen self test in the sunshine, a few days prior to your trip. Because the last thing you want is for your day to be ruined by a sunscreen allergy.